Slice it any way you want: “American Reunion,” the fourth theatrical installment of the “American Pie” film franchise, is the same expected dish that’s been served to moviegoers for years. There’s no whip cream dollop or vanilla ice cream scoop or streusel topping to sweeten the deal. The sequel does, however, feature the entire original cast for the first time since 1999, which proves valuable for those fans who enjoy nostalgia and want to see the series wrap up fittingly. Unless there’s a compelling reason to shoot a fifth movie and call it “American Funeral,” “Reunion” should satisfy that expectation.

Ignore the fact that the characters are rallying together for their 13-year reunion (“they missed the 10-year by a couple” is the unconvincing reason given about why they didn’t get together in 2009) – the crop of sexually charged, baby-faced teens from the ’90s are all grown up with real responsibilities. With the exception of everyone’s favorite douchebag Steve Stifler (Seann William Scott), the gang has also become a lot more mature. Besides keeping the baked good safe from penetration, this little leap into adulthood turns Reunion, even more than 2003’s “American Wedding,” into the Stifler Show.

Scott, who along with actor John Cho (“Star Trek”) has had the most successful career of all the cast members post-“Pie”, owns his character, which is probably why a majority of the jokes and gags involve him in some smutty way. Stifler hasn’t evolved much, and no one wants him to. All will be right with the raunchy-comedy world if at the age of 80 Stifler has advanced into the dirty-old-man stage.

There are plenty of other mainstays to consider if searching for more thoughtful character development, like lovable loser Jim (Jason Biggs), who is trying to be a respectable husband and father, and Jim’s dad (Eugene Levy), who is now a widow. It’s a sentimental departure by directors/writers Jon Hurwitz and Hayden Schlossberg (the “Harold & Kumar” trilogy) that occasionally works well when combined with some funny memories and set pieces from the kids’ high school days.

But again, it’s the scene-stealing Stifler who commands the screen for better or worse. No matter how old he gets, he’s exudes the frat boy variety of misogynistic tendencies, which don’t seem to bother anyone since he’s such a moron. Lose him, and there would be no reason for this franchise to exist. What would Tara Reid do then?